Gametogenesis is a complex and sex-specific multistep process during which the gonadal somatic niche plays an essential regulatory role. One of the most crucial steps during human female... Show moreGametogenesis is a complex and sex-specific multistep process during which the gonadal somatic niche plays an essential regulatory role. One of the most crucial steps during human female gametogenesis is the formation of primordial follicles, the functional unit of the ovary that constitutes the pool of follicles available at birth during the entire reproductive life. However, the relation between human fetal germ cells (hFGCs) and gonadal somatic cells during the formation of the primordial follicles remains largely unexplored. We have discovered that hFGCs can form multinucleated syncytia, some connected via interconnecting intercellular bridges, and that not all nuclei in hFGC–syncytia were synchronous regarding meiotic stage. As hFGCs progressed in development, pre-granulosa cells formed protrusions that seemed to progressively constrict individual hFGCs, perhaps contributing to separate them from the multinucleated syncytia. Our findings highlighted the cell–cell interaction and molecular dynamics between hFGCs and (pre)granulosa cells during the formation of primordial follicles in humans. Knowledge on how the pool of primordial follicle is formed is important to understand human infertility. Show less
Krop, J.; Zwan, A. van der; Ijsselsteijn, M.E.; Kapsenberg, H.; Luk, S.J.; Hendriks, S.H.; ... ; Eikmans, M. 2022
Although the immunological complexity of the maternal-fetal interface is well appreciated, the actual interaction of maternal immune cells and fetal trophoblasts is insufficiently understood. To... Show moreAlthough the immunological complexity of the maternal-fetal interface is well appreciated, the actual interaction of maternal immune cells and fetal trophoblasts is insufficiently understood. To comprehend the composition and spatial orientation of maternal immune cells and fetal extravillous trophoblasts, we applied imaging mass cytometry on decidua basalis of the three trimesters of healthy pregnancy. Within all trimesters, we observed considerably higher frequencies of myeloid cells in the decidua than is seen with single-cell suspension techniques. Moreover, they were the most pronounced cell type in the microenvironment of other decidual cells. In first trimester, HLA-DR- macrophages represented the most abundant myeloid subcluster and these cells were frequently observed in the vicinity of trophoblasts. At term, HLA-DR+ macrophage subclusters were abundantly present and frequently observed in the microenvironment of T cells. Taken together, our results highlight the dynamic role of myeloid cells at the human maternal-fetal interface throughout gestation. Show less
Giesbers, S.; Bos, M.; Bulten, J.; Meeren, L. van der; Drongelen, J. van 2022
BackgrounBackground: Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a rare fetal disease in which maternal antibodies directed toward fetal human platelet antigens (HPA) are formed... Show moreBackgrounBackground: Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a rare fetal disease in which maternal antibodies directed toward fetal human platelet antigens (HPA) are formed during pregnancy and cause fetal thrombocytopenia. The diagnosis FNAIT is suspected when a fetus or neonate presents with signs of bleeding. Case: We describe a pregnancy complicated by a placental hematoma in the 20th week of gestation as the first manifestation of FNAIT. Further evaluation showed signs of germinal matrix hemorrhage and HPA-5b allo-antibodies. After the diagnosis, intravenous immunoglobulin was administered weekly and a healthy daughter was born at 37 weeks. Histopathological analysis revealed that the hematoma was caused by a sub-amniotic hemorrhage of fetal origin. Conclusion: A subamniotic hematoma appears to be the first manifestation of FNAIT. (c) 2022 The Author(s). Published by S. Karger AG, Basel Show less
